KRAS and TP53 mutations are the two most common driver mutations in patients with lung adenocarcinoma (LUAD), and they appear to reduce latency and increase metastatic proclivity when a KRAS and TP53 co-mutation (KRAS/TP53-mut) occurs. However, the molecular mechanism involved is unclear. N⁶-methyladenosine (m⁶A), the most abundant RNA modification in mammal mRNAs, plays a critical role in tumorigenesis. Here, we used genomic and transcriptomic data and found that only LUAD patients with KRAS/TP53-mut, but not an individual mutation, appeared to exhibit poor overall survival when compared with patients without KRAS and TP53 mutation (wildtype). Subsequently, we analyzed the differential expression of the 15-m⁶A-related genes in LUAD with different mutations and found that YTHDF1 was the most upregulated in KRAS/TP53-mut patients and associated with their adverse prognosis. Bioinformatics and experimental evidence indicated that elevated YTHDF1 functionally promoted the translation of cyclin B1 mRNA in an m⁶A-dependent manner, thereby facilitating the tumor proliferation and poor prognosis of LUAD with KRAS/TP53-mut. Furthermore, the concurrent increase in YTHDF1 and cyclin B1 was confirmed by immunohistochemistry staining in patients with co-occurring KRAS/TP53 mutations. YTHDF1 was correlated with an unfavorable clinical stage and tumor size. Collectively, we identified and confirmed a novel “YTHDF1–m⁶A–cyclin B1 translation” axis as an essential molecular pathway for the prognosis of KRAS/TP53-mut LUAD.

Atherosclerosis (AS) is the leading cause of cardiovascular diseases (CVDs) with a high rate of mortality worldwide. Plasma cell-free DNA (cfDNA), mainly originating from apoptosis, necrosis, and active secretion, has been recognized as a promising biomarker for the diagnosis and prognosis of multiple cancers, whereas there are no reports about cfDNA in CVDs. Here, we found an increased quantity and decreased integrity of cfDNA (cfDI) in the serum from AS patients compared with normal controls. Moreover, the reduced cfDI is inversely correlated with serum LDL levels, carotid plaque size, and carotid plaque thickness in the progression of AS. Consistently, in vivo experiments confirmed that the release and cleavage of cfDNA were increased concomitantly with the development and progression of AS in ApoE⁻/⁻ mice. Our study sheds light on the potential of cfDNA and cfDI as molecular biomarkers for detecting and monitoring AS.

MicroRNA-92a (miR-92a) may serve as a novel promising biomarker in multiple cancers, including colorectal cancer (CRC); however, the diagnostic accuracy and the underlying molecular mechanism of miR-92a in CRC is poorly understood. We first carried out meta-analysis and found that serum/plasma miR-92a yield better diagnostic efficacy when compared to stool samples and CRC tissues, and this finding was validated by our independent study through stool sample. Multiple bioinformatics assay indicated that miR-92a expression was positively correlated with heterogeneous nuclear ribonucleoproteins A2/B1 (HNRNPA2B1) expression and closely related with the clinical characteristics of CRC. Experimental evidence showed that knockdown of HNRNPA2B1 could significantly decrease miR-92a expression and secretion in RKO cells. HNRNPA2B1 mediated miR-92a via m6A RNA modification. These findings indicate that HNRNPA2B1-m6A RNA modification-derived MicroRNA-92a upregulation and section from the local CRC acts a candidate noninvasive serum biomarker in colorectal cancer. Our study provides a novel insight into miR-92a mechanisms in relation to both expression and secretion for CRC diagnosis.